diff options
Diffstat (limited to 'drivers/gles2/shaders/ssao.glsl')
| -rw-r--r-- | drivers/gles2/shaders/ssao.glsl | 160 |
1 files changed, 74 insertions, 86 deletions
diff --git a/drivers/gles2/shaders/ssao.glsl b/drivers/gles2/shaders/ssao.glsl index 219f0957e0..8dbe8c6ba9 100644 --- a/drivers/gles2/shaders/ssao.glsl +++ b/drivers/gles2/shaders/ssao.glsl @@ -1,12 +1,11 @@ [vertex] - -layout(location=0) in highp vec4 vertex_attrib; +layout(location = 0) in highp vec4 vertex_attrib; void main() { gl_Position = vertex_attrib; - gl_Position.z=1.0; + gl_Position.z = 1.0; } [fragment] @@ -43,19 +42,20 @@ void main() { // This is the number of turns around the circle that the spiral pattern makes. This should be prime to prevent // taps from lining up. This particular choice was tuned for NUM_SAMPLES == 9 -const int ROTATIONS[] = int[]( 1, 1, 2, 3, 2, 5, 2, 3, 2, -3, 3, 5, 5, 3, 4, 7, 5, 5, 7, -9, 8, 5, 5, 7, 7, 7, 8, 5, 8, -11, 12, 7, 10, 13, 8, 11, 8, 7, 14, -11, 11, 13, 12, 13, 19, 17, 13, 11, 18, -19, 11, 11, 14, 17, 21, 15, 16, 17, 18, -13, 17, 11, 17, 19, 18, 25, 18, 19, 19, -29, 21, 19, 27, 31, 29, 21, 18, 17, 29, -31, 31, 23, 18, 25, 26, 25, 23, 19, 34, -19, 27, 21, 25, 39, 29, 17, 21, 27 ); +const int ROTATIONS[] = int[]( + 1, 1, 2, 3, 2, 5, 2, 3, 2, + 3, 3, 5, 5, 3, 4, 7, 5, 5, 7, + 9, 8, 5, 5, 7, 7, 7, 8, 5, 8, + 11, 12, 7, 10, 13, 8, 11, 8, 7, 14, + 11, 11, 13, 12, 13, 19, 17, 13, 11, 18, + 19, 11, 11, 14, 17, 21, 15, 16, 17, 18, + 13, 17, 11, 17, 19, 18, 25, 18, 19, 19, + 29, 21, 19, 27, 31, 29, 21, 18, 17, 29, + 31, 31, 23, 18, 25, 26, 25, 23, 19, 34, + 19, 27, 21, 25, 39, 29, 17, 21, 27); //#define NUM_SPIRAL_TURNS (7) -const int NUM_SPIRAL_TURNS = ROTATIONS[NUM_SAMPLES-1]; +const int NUM_SPIRAL_TURNS = ROTATIONS[NUM_SAMPLES - 1]; uniform sampler2D source_depth; //texunit:0 uniform highp usampler2D source_depth_mipmaps; //texunit:1 @@ -90,44 +90,41 @@ vec3 reconstructCSPosition(vec2 S, float z) { } vec3 getPosition(ivec2 ssP) { - vec3 P; - P.z = texelFetch(source_depth, ssP, 0).r; + vec3 P; + P.z = texelFetch(source_depth, ssP, 0).r; - P.z = P.z * 2.0 - 1.0; + P.z = P.z * 2.0 - 1.0; #ifdef USE_ORTHOGONAL_PROJECTION - P.z = ((P.z + (camera_z_far + camera_z_near)/(camera_z_far - camera_z_near)) * (camera_z_far - camera_z_near))/2.0; + P.z = ((P.z + (camera_z_far + camera_z_near) / (camera_z_far - camera_z_near)) * (camera_z_far - camera_z_near)) / 2.0; #else - P.z = 2.0 * camera_z_near * camera_z_far / (camera_z_far + camera_z_near - P.z * (camera_z_far - camera_z_near)); + P.z = 2.0 * camera_z_near * camera_z_far / (camera_z_far + camera_z_near - P.z * (camera_z_far - camera_z_near)); #endif - P.z = -P.z; + P.z = -P.z; - // Offset to pixel center - P = reconstructCSPosition(vec2(ssP) + vec2(0.5), P.z); - return P; + // Offset to pixel center + P = reconstructCSPosition(vec2(ssP) + vec2(0.5), P.z); + return P; } /** Reconstructs screen-space unit normal from screen-space position */ vec3 reconstructCSFaceNormal(vec3 C) { - return normalize(cross(dFdy(C), dFdx(C))); + return normalize(cross(dFdy(C), dFdx(C))); } - - /** Returns a unit vector and a screen-space radius for the tap on a unit disk (the caller should scale by the actual disk radius) */ -vec2 tapLocation(int sampleNumber, float spinAngle, out float ssR){ - // Radius relative to ssR - float alpha = (float(sampleNumber) + 0.5) * (1.0 / float(NUM_SAMPLES)); - float angle = alpha * (float(NUM_SPIRAL_TURNS) * 6.28) + spinAngle; +vec2 tapLocation(int sampleNumber, float spinAngle, out float ssR) { + // Radius relative to ssR + float alpha = (float(sampleNumber) + 0.5) * (1.0 / float(NUM_SAMPLES)); + float angle = alpha * (float(NUM_SPIRAL_TURNS) * 6.28) + spinAngle; - ssR = alpha; - return vec2(cos(angle), sin(angle)); + ssR = alpha; + return vec2(cos(angle), sin(angle)); } - /** Read the camera-space position of the point at screen-space pixel ssP + unitOffset * ssR. Assumes length(unitOffset) == 1 */ vec3 getOffsetPosition(ivec2 ssC, vec2 unitOffset, float ssR) { - // Derivation: - // mipLevel = floor(log(ssR / MAX_OFFSET)); + // Derivation: + // mipLevel = floor(log(ssR / MAX_OFFSET)); int mipLevel = clamp(int(floor(log2(ssR))) - LOG_MAX_OFFSET, 0, MAX_MIP_LEVEL); ivec2 ssP = ivec2(ssR * unitOffset) + ssC; @@ -138,13 +135,12 @@ vec3 getOffsetPosition(ivec2 ssC, vec2 unitOffset, float ssR) { // Manually clamp to the texture size because texelFetch bypasses the texture unit ivec2 mipP = clamp(ssP >> mipLevel, ivec2(0), (screen_size >> mipLevel) - ivec2(1)); - if (mipLevel < 1) { //read from depth buffer P.z = texelFetch(source_depth, mipP, 0).r; P.z = P.z * 2.0 - 1.0; #ifdef USE_ORTHOGONAL_PROJECTION - P.z = ((P.z + (camera_z_far + camera_z_near)/(camera_z_far - camera_z_near)) * (camera_z_far - camera_z_near))/2.0; + P.z = ((P.z + (camera_z_far + camera_z_near) / (camera_z_far - camera_z_near)) * (camera_z_far - camera_z_near)) / 2.0; #else P.z = 2.0 * camera_z_near * camera_z_far / (camera_z_far + camera_z_near - P.z * (camera_z_far - camera_z_near)); @@ -153,78 +149,74 @@ vec3 getOffsetPosition(ivec2 ssC, vec2 unitOffset, float ssR) { } else { //read from mipmaps - uint d = texelFetch(source_depth_mipmaps, mipP, mipLevel-1).r; - P.z = -(float(d)/65535.0)*camera_z_far; + uint d = texelFetch(source_depth_mipmaps, mipP, mipLevel - 1).r; + P.z = -(float(d) / 65535.0) * camera_z_far; } - // Offset to pixel center P = reconstructCSPosition(vec2(ssP) + vec2(0.5), P.z); return P; } - - /** Compute the occlusion due to sample with index \a i about the pixel at \a ssC that corresponds - to camera-space point \a C with unit normal \a n_C, using maximum screen-space sampling radius \a ssDiskRadius + to camera-space point \a C with unit normal \a n_C, using maximum screen-space sampling radius \a ssDiskRadius - Note that units of H() in the HPG12 paper are meters, not - unitless. The whole falloff/sampling function is therefore - unitless. In this implementation, we factor out (9 / radius). + Note that units of H() in the HPG12 paper are meters, not + unitless. The whole falloff/sampling function is therefore + unitless. In this implementation, we factor out (9 / radius). - Four versions of the falloff function are implemented below + Four versions of the falloff function are implemented below */ -float sampleAO(in ivec2 ssC, in vec3 C, in vec3 n_C, in float ssDiskRadius,in float p_radius, in int tapIndex, in float randomPatternRotationAngle) { - // Offset on the unit disk, spun for this pixel - float ssR; - vec2 unitOffset = tapLocation(tapIndex, randomPatternRotationAngle, ssR); - ssR *= ssDiskRadius; +float sampleAO(in ivec2 ssC, in vec3 C, in vec3 n_C, in float ssDiskRadius, in float p_radius, in int tapIndex, in float randomPatternRotationAngle) { + // Offset on the unit disk, spun for this pixel + float ssR; + vec2 unitOffset = tapLocation(tapIndex, randomPatternRotationAngle, ssR); + ssR *= ssDiskRadius; - // The occluding point in camera space - vec3 Q = getOffsetPosition(ssC, unitOffset, ssR); + // The occluding point in camera space + vec3 Q = getOffsetPosition(ssC, unitOffset, ssR); - vec3 v = Q - C; + vec3 v = Q - C; - float vv = dot(v, v); - float vn = dot(v, n_C); + float vv = dot(v, v); + float vn = dot(v, n_C); - const float epsilon = 0.01; - float radius2 = p_radius*p_radius; + const float epsilon = 0.01; + float radius2 = p_radius * p_radius; - // A: From the HPG12 paper - // Note large epsilon to avoid overdarkening within cracks - //return float(vv < radius2) * max((vn - bias) / (epsilon + vv), 0.0) * radius2 * 0.6; + // A: From the HPG12 paper + // Note large epsilon to avoid overdarkening within cracks + //return float(vv < radius2) * max((vn - bias) / (epsilon + vv), 0.0) * radius2 * 0.6; - // B: Smoother transition to zero (lowers contrast, smoothing out corners). [Recommended] - float f=max(radius2 - vv, 0.0); - return f * f * f * max((vn - bias) / (epsilon + vv), 0.0); + // B: Smoother transition to zero (lowers contrast, smoothing out corners). [Recommended] + float f = max(radius2 - vv, 0.0); + return f * f * f * max((vn - bias) / (epsilon + vv), 0.0); - // C: Medium contrast (which looks better at high radii), no division. Note that the - // contribution still falls off with radius^2, but we've adjusted the rate in a way that is - // more computationally efficient and happens to be aesthetically pleasing. - // return 4.0 * max(1.0 - vv * invRadius2, 0.0) * max(vn - bias, 0.0); + // C: Medium contrast (which looks better at high radii), no division. Note that the + // contribution still falls off with radius^2, but we've adjusted the rate in a way that is + // more computationally efficient and happens to be aesthetically pleasing. + // return 4.0 * max(1.0 - vv * invRadius2, 0.0) * max(vn - bias, 0.0); - // D: Low contrast, no division operation - // return 2.0 * float(vv < radius * radius) * max(vn - bias, 0.0); + // D: Low contrast, no division operation + // return 2.0 * float(vv < radius * radius) * max(vn - bias, 0.0); } - - void main() { - // Pixel being shaded ivec2 ssC = ivec2(gl_FragCoord.xy); // World space point being shaded vec3 C = getPosition(ssC); -/* if (C.z <= -camera_z_far*0.999) { - // We're on the skybox - visibility=1.0; - return; - }*/ + /* + if (C.z <= -camera_z_far*0.999) { + // We're on the skybox + visibility=1.0; + return; + } + */ //visibility=-C.z/camera_z_far; //return; @@ -251,7 +243,7 @@ void main() { #endif float sum = 0.0; for (int i = 0; i < NUM_SAMPLES; ++i) { - sum += sampleAO(ssC, C, n_C, ssDiskRadius, radius,i, randomPatternRotationAngle); + sum += sampleAO(ssC, C, n_C, ssDiskRadius, radius, i, randomPatternRotationAngle); } float A = max(0.0, 1.0 - sum * intensity_div_r6 * (5.0 / float(NUM_SAMPLES))); @@ -271,10 +263,10 @@ void main() { sum = 0.0; for (int i = 0; i < NUM_SAMPLES; ++i) { - sum += sampleAO(ssC, C, n_C, ssDiskRadius,radius2, i, randomPatternRotationAngle); + sum += sampleAO(ssC, C, n_C, ssDiskRadius, radius2, i, randomPatternRotationAngle); } - A= min(A,max(0.0, 1.0 - sum * intensity_div_r62 * (5.0 / float(NUM_SAMPLES)))); + A = min(A, max(0.0, 1.0 - sum * intensity_div_r62 * (5.0 / float(NUM_SAMPLES)))); #endif // Bilateral box-filter over a quad for free, respecting depth edges // (the difference that this makes is subtle) @@ -286,8 +278,4 @@ void main() { } visibility = A; - } - - - |